REGRESSION: Yes, in 4.17, the following warning occurs instead:
If the user packages a project with an exclusively nativized blueprint and a map select to include in a packaged build, the following error will occur:
NOTE: This doesn't occur if there isn't a map select to package, but I don't get the warning above either.
Build fails with error.
Build succeeds with warning (see description).
There's no existing public thread on this issue, so head over toAnswerHub just mention UE-51373 in the post.